Exhaust muffler with conical baffle plates



Nov. 13, 1951 G. PLASSE EXHAUST MUFFLER WITH CONICAL BAFFLE PLATES FiledOct. 22, 1947 JNVENTOR. W PM BY W A W? p M F Patented Nov. 13, 1951UNITED STATES PATENT OFFICE EXHAUST MUFFLERWI'I'H CONICAL BAFFLE PLATES1 Claim.- 1

Internal combustion engines often rotate at a very high speed say 5 to6,000 R. P. M. The exhausting of the gases at said rate of runningshould be operated in an extremely rapid manner so as not to produce anycounter-pressure in the exhaust which counter-pressure may reduce thepower of the engine by to In order to remove said drawbacks, thie tuelused exclusively in such engines is the so-called superfuel providingburnt gases the specific weight of which is about 6 times less than inthe case of ordinary gasoline.

In spite of this there always occurs a braking of the engine whichknocks at highspeed and often self-ignition is produced by reason of thefaulty closing of the exhaust valves, due to the pressure to which theyare submitted. Certain engine builders have attempted to solve theproblem by reducing as much as possible the silencer device but in thecase of an automobile vehicle, more particularly with a metal bodyworkforming a resonant box, the continuous amplified noise of the exhaustgases is unbearable for the driver and for the passengers.

The apparatus forming the object of my invention removes these drawbacksand ensures at the highest speeds the rapid and silent exhaust of theburnt gases.

This result is obtained by associating streamlined bafiie platesprovided with a plurality of openings arranged along similar helicallines on all the baffle plates or else said openings are arranged inreverse formation. This system produces an eddying of the burnt gaseswhich are no longer held back but on the contrary sucked outwardly bythe depression produced.

This exhaust is still further accelerated by an arrangement fitted atthe outer end of the silencer and producing an annular current of airthat is proportional to the speed of the vehicle and sucks in a stillfurther amount of gases.

This large amount of air is stirred with the smokes which are thusdiluted and decomposed and the residuum passing out of the silencer hasno longer the obnoxious character and unpleasant smell that it had notbeen possible heretofore to remove.

Engines thus equipped yield their highest efiiciency even with ordinarygasoline which leads to an increase in the speed of the vehicle and toan economy in fuel.

In accompanying drawings given out by way of example in a diagrammaticmanner and without any binding sense I have illustrated several forms ofexecution of the invention.

Fig. 1 is a front View partly torn off of a silencer for motor-cycles.

Fig. 2 shows a silencer for an automobile.

Fig. 3 is a sectional View of a silencer with a twin pipe for trucks orinternal combustion engines having a high cylinder volume.

Fig. 4' is an axial cross-section of a supplementary arrangement securedto the end of the silencer for accelerating the exhaust of the burntgases.

Fig. 5 is a detail view of two types of cones playing the part of bafileplates in the silencer.

The apparatus illustrated in said drawings includes a tube 1 for theexpansion of the gases, said tube being adapted to be secured to theexhaust pipe. Inside said tube are arranged conical members 2 of metalsheet. These cones are placed either in parallelism with one another orin relative reverse position or else they are secured together throughtheir base; they are provided with longitudinal slots separated from oneanother and established so as to form a sort of helical pitch which mayhave the same direction on each cone or else be reversed from one coneto the next.

The slots 3 are formed in the mass of the cone and the metal is urgedoutwardly when the cones are intended to receive gases through theinside and on the contrary towards the inside when the cones show theirapex against the flow of gas.

The arrangement illustrated in Fig. 1 comprises four cones of which oneis located at the input into the expansion tube and two are coupledthrough their base, the latter being directed towards the outlet of thetube.

The apparatus shown in Fig. 2 is designed for automobile vehicles and isalso provided with four cones arranged in the same manner as in theapparatus shown in Fig. l but the two central cones coupled throughtheir base are separated by a gap from the two other cones of opposeddirection.

The apparatus shown in Fig. 3 is intended more particularly for use onlarge automobiles and trucks. It includes two arrangements similar tothat illustrated in Fig. 2 arranged in twin formation and associatedwith a single input and a single output. Obviously the inputs or outputsof the gases may as well be provided independently for each arrangement.

For very powerful engines, it is possible to couple a plurality of suchapparatuses in order to do away with large cross-sections in theexpansion tubes.

The arrangement illustrated in Fig. 4 is intended for location at theend of the exhaust pipe corresponding to the output of the gases. Itappears under the shape of a funnel 6 inside which is housed a portionof a tube held by the stays I. Said tube 5 serves only as a securingmeans for the exhaust pipe and does not reach the end of the funnel.Thus there is pro-' vided between the tube 5 and the walls of the funnelan empty annular space through which the outer air enters with a speedproportional to that of the vehicle. The inner end of-the funnel forms athrottle which furthers the stirring of the air and gases. The base ofthe funnel is welded or secured through any other suitable means to afinal chamber of suitable shape thatis perforated and opens into theouter atmos-' phere and into which the mixture of air and smokes arrivesand is thenafter removed out- V rangement of the slots Without modifyingtherebythe principle of the invention as defined in ao-' companyingclaim.

What I claim is; An exhaust muffler for internal combustion:

engines comprising an expansion pipe, conical bafile plates openingtowards the inlet and outlet respectively and at least one intermediarydouble cone baflle plate, the bases of the cones of Whichare inunrestrictedly open contacting relationship and engage through theirouter periphery the inside of the expansion pipe wall, the differentbaflle plates being provided with a plurality of series of slots lyingat short distances 'from one another along substantially helical lines.

l GUSTAVE PLASSE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 938,101 Winters Oct. 26, 19091,859,400 Kersey v May 24, 1932 2,024,834 Rippe Dec. 17, 1935 2,051,675Blanchard Aug. 8, 1936 2,065,343 Moore Dec. 22, 1936 2,122,086 ChaseJune 28, 1938 FOREIGN PATENTS Number Country Date 552,142 France Apr.24, 1923 357,597 Italy Mar. 22, 1938

